1. Field of the Invention
The present invention relates to an image-processing device for processing image data, and an image-processing method and image-processing program that can be used by the image-processing device.
2. Related Art
When printing an image based on image data read by a scanner or acquired through other means, image processing has conventionally been performed using spatial filters to remove noise components from the image.
For example, halftone images read by a scanner often include a noise component that can lead to moiré or the like. Therefore, scanned image data is commonly passed through a spatial filter capable of removing (or at least reducing) the noise component prior to printing.
Japanese unexamined patent application publication No. HEI-7-111602 proposes an image-forming device configured to determine whether or not an image represented by acquired image data is a halftone image (setting the output of a halftone-dot separating unit to “H” or “L”) and switch the characteristics of a spatial filter to be used on the image data targeted for output according to the results of the determination. Hence, the image-forming device can remove noise components in accordance with the acquired image.